Functions of exogenous application of connective tissue growth factor in stimulating human dermal papilla cells and human hair follicle outer root sheath cells for reconstructive tissue-engineering hair follicles

Zhonghua Yi Xue Za Zhi. 2013 Apr 9;93(14):1063-6.
[Functions of exogenous application of connective tissue growth factor in stimulating human dermal papilla cells and human hair follicle outer root sheath cells for reconstructive tissue-engineering hair follicles].

Zhang PP, Chai JK, Wang JP, Duan HJ, Ma L, Zhu GY.

Department of Burns and Plastic Surgery, First Affiliated Hospital, General Hospital of PLA, Beijing 100048, China.

OBJECTIVE:
To explore the functions of connective tissue growth factor (CTGF) in the restoration of hair follicles with a mixture of human dermal papilla cells and human hair follicle outer root sheath cells in vitro in nude mice.
METHODS:
Human hair follicle outer root sheath cells (hfORS) and human hair dermal papilla cells (hDP) were cultured in vitro and mixed in a fixed ratio (hfORS: hDP = 5:1). Flow cytometry was used to detect the content of CD200(+) cells in human hair follicle outer root sheath cells.And 8 nude mice were divided randomly into 2 groups according to a random number table and back wounds produced. Group A was transplanted with cell mixture plus 20 µg/L CTGF. Group B was transplanted with cell mixture alone. After 8 weeks of transplantation, the development of hair follicle formation was observed histologically.PCR was used to detect the expression of human specific DNA and mice DNA in transplants.
RESULTS:
The portion of CD200(+) cells in cultured hfORS was 19.65%. At 8 weeks after implantation, hair follicle formation could be observed in Group A (268 ± 96) more than Group B (62 ± 20). The difference was statistically significant (P < 0.05). And PCR showed that there was human composition in transplant.
CONCLUSION:
CTGF can induce the formation of hair follicle by promoting the interference between hDP and hfORS.

Great info, CS.

I don't want to champion the heat theory too much, as it's entirely likely that there are more factors that cause mpb within certain men, it's just that I've only ever lost hair when my scalp has overheated, yet many men go completely bald when they're only 18, so it would seem that follicles are genetically programmed to shrink in certain cases. My mpb is likely an epigenetic issue caused largely by the thermal factor. I guess this could be compared to type II diabetes in that respect.

Regarding the thermal issue, I think that cells have a tolerance threshold, and when that threshold has been surpassed too often tissue is at risk of hyperthermia, therefore epigenetic changes likely occur within the genome. In this respect, hair becomes a hindrance in releasing heat from the skin, so growth factors are 'switched off' within the papilla, and conversely, growth factors are increased in sweat glands, as to provide better cooling from respective tissues. This seemed to be why our primate ancestors began losing most body hair, and reversely, why hirsutism develops in anorexics who are at risk of hypothermia.